1. Field of the Invention
This invention relates in general to certain new and useful improvements in fluid-dynamic efficiency of wings and fluid-dynamic foils which are employed in dual or multiple foil structures or in joined segments of foils that are split into segments and rejoined.
2. Description of the Prior Art
Airfoil shapes and foils moving through a fluid produce pressure differential as roughly defined by the term xe2x80x9cliftxe2x80x9d. By producing pressure differential, a pattern of circulation is produced around the advancing foil. This circulation is continuous around the length of the foil and is known as a xe2x80x9cvortexxe2x80x9d, or xe2x80x9cvortical flowxe2x80x9d. This vortex remains xe2x80x9cboundxe2x80x9d around a conventional airfoil the length of the surface from root to the tip. The same phenomenon occurs with all fluid foils creating pressure differentials similar to lift. Beyond the tip of conventional fluid foils this rotating fluid circulation xe2x80x9cshedsxe2x80x9d off into tornado-like xe2x80x9cfreexe2x80x9d vortices or, in the case of aircraft a trailing xe2x80x9cwingtip vortex.xe2x80x9d Each shed vortex tends to grow into a tighter and more compact rotating fluid mass as it leaves each tip surface into the xe2x80x9cfree streamxe2x80x9d because the differential in pressures (lower pressure from the upper side of the foil and higher pressure from the opposite side of the foil) are attempting to equalize. The vortex, with its high-pressure outer layers rotating rapidly, draws the high-pressure component into its lower pressure core. This suction-creating effect produces undesirable lift-induced drag. The pair of shed tip vortices typically trailing behind conventional aircraft exemplifies this. When in flight, small vortices also shed from the trailing edge of conventional aircraft wings, but the primary drag-inducing vortices are those shed at the outer wingtips. These vortices contain tremendous quantities of rotating mass fluid-dynamic energy.
Long tornado-like rotating vortices behind large aircraft may continue for hundreds of feet or even miles, depending upon the weight of the aircraft, wing area, aspect ratio, and other variable factors. In some cases these vortices endanger other aircraft that may be entering the wake of these energy-laden vortices trailing the aircraft. It becomes obvious that trailing vortices in addition to creating tremendous amounts of fluid-dynamic drag also can be hazardous to pilots and passengers flying small aircraft where larger aircraft are departing and arriving.
Reducing induced drag results directly in decreasing the amount of energy required to sustain fluid-dynamic foil induced lift The purpose of all attempts to reduce drag is energy conservation of one form or another. Some inventors have sought to reduce induced vortice-created drag in aircraft by use of such devices as end plates, winglets at wing tips, propellers with winglet-like projections at the blade tips. Some inventors have sought to improve aerodynamic efficiency by using joined wing systems on conventional fuselages. Joined wings have inherent rigidity and some fluid-dynamic advantage over conventional wings, but there are inherent inefficiencies in prior art joined wing systems in that they do not employ devices that would eliminate or greatly reduce the drag penalty from vortex-induced drag. Up to xc2xd or more of all induced drag of conventional wings is due to xe2x80x9cvortex sheddingxe2x80x9dxe2x80x94the resulting creation of free vortices from fluid-dynamic foils in the process of producing lift.
Most the multi-wing creations of previous inventors have not reached the maximum potential of aerodynamic efficiency and drag reduction. In spite of the positive (theoretically and experientially demonstrated) potential of joined wing aircraft to reduce induced drag, most joined wing aircraft have wing intersections that unfavorably translate wing tip pressures from the leading wing to the following wing. Forward placed airfoils are commonly joined to aft ones such that vortice translation creates oppositional interference when translated pressure mass from the first airfoil interfaces with counter-rotating circulation mass of the subsequent foil. One advantage of structurally joining wingtips is a shorter, yet stronger span for the same amount of wing area. Decreased wing length results in decreased bending moments. When a wingtip union is properly designed to translate the circulating fluid mass without letting it shed as a vortex, it can also be designed to utilize this potential energy for forward thrust and lift augmentation to the rear lifting surfaces (in a joined wing, biplane system or multilayered wing arrangement). The ideal wing system would reduce overall induced drag rather than creating unwanted induced vortex drag. Utilizing such an invention would enable a designer to significantly reduce wing area because the wing system is producing more lift per square area unit. Reducing wing area also means less profile drag and the amount of energy necessary to sustain forward flight is greatly decreased. The ultimate improvement of aerodynamic or fluid dynamic foils would be to eliminate practically all foil-tip vortex-induced drag by translating this fluid-dynamic flow from a leading foil pair to corresponding surfaces of subsequent foils behind said leading foil pair, or to convert this vortical energy into forward thrust, or both. The ultimate increase in efficiency would result from utilizing inventions which eliminate the greater percentage of all wingtip vortex-induced drag, thus the effect of xe2x80x9cinfinitexe2x80x9d wing is more nearly realized without the more extensive structure and subsequent weight penalty resulting from strengthening and lengthening wings to a high aspect ratio.
Vortex shedding at the wingtips is a performance liability for conventional aircraft: Shedding wingtip vortices produce xc2xd or more of the total induced drag of lifting airfoils (wings and propeller blades). Shedding vortices are what causes increased noise from rotating blades and propellers. Inventions such as the xe2x80x9cQ-Tipxe2x80x9d propeller modify shedding vortices to minimize noise produced at the tips. Other inventions have been created for use on conventional aircraft wingtips and propellers to reduce drag and utilize the dynamic energy contained in these vortices. Such inventions reduce the drag-producing component by xe2x80x9cdiffusingxe2x80x9d or xe2x80x9cdissipatingxe2x80x9d or xe2x80x9csuppressingxe2x80x9d these vortices. xe2x80x9cWhitecomb Wingletsxe2x80x9d or Hachett""s Vortex Diffuser (U.S. Pat. No. 4,190,219) were each designed to disperse the vortex somewhat and also convert vortical energy into forward thrust. Small winglets such as these can improve wing efficiency somewhere near 15%. Most devices that are designed for conventional wings to disperse, reduce, or utilize tip vortice dynamic pressures function with varying, but limited degrees of efficiency in drag reduction. Previous attempts to significantly reduce drag due to vortex shedding have produced limited degrees of success.
Methods of modifying the wingtip vortex formed at the outer tips of airfoils have included the use of end plates to reduce vortex shedding and multiple vanes to xe2x80x9csplitxe2x80x9d, xe2x80x9cdiffusexe2x80x9d or weaken the vortex, thus lessening vortex-induced drag. Attached panels and upward or downward turned tips have been used with varying degrees of success to present. Some inventions break larger vortices down into multiple smaller vortices to lessen vortex-induced drag, thus not allowing a single trailing vortex to form off each wingtip. Such devices are attempts to reduce kinetic energy in the wake of the wing, and consequently lessen induced drag. Richard Vogt (1951, U.S. Pat. No. 2,576,981), Alexander Lippish (1956 U.S. Pat. No. 2,743,888), Clarence C. Cone, Jr. (1966 U.S. Pat. No. 3,270,988), and Scott Rethorst (1973 U.S. Pat. No. 3,712,564) each invented wingtip devices to diminish vortex-induced drag in aircraft. Nonetheless, such attempts have produced only limited improvement in induced drag reduction.
Dr. Richard T. Whitcomb of NASA (inventor/developer of the xe2x80x9cVWhitcomb Wingletxe2x80x9d) in his presentation of CONCEPTS FOR DRAG REDUCTION OF AGARD/VKI outlined the problem and suggested solutions and objectives in the section entitled xe2x80x9cMethods for Reducing Subsonic Drag Due to Lift.xe2x80x9d To utilize more effective methods of vortex-induced drag reduction and improve wing efficiency has been the objective of certain inventors who perceive that joined wing systems could be more efficient, could have better structural strength-to-weight ratio, and could provide better crash protection for passengers and pilot. Such aircraft employ dual airfoils (i.e. forward and aft pairs of wings) joined structurally such that united members ideally create little or no aerodynamic interference or even contribute to aerodynamic function by use of control surfaces, with unions that add rigidity and strength to the wing structure. Without additional special structure that changes fluid dynamic flow characteristics, joined wing systems produce only marginal drag reduction results.
Geraci (U.S. Pat. No. 2,576,294) showed a box plane configuration. Outer wingtip unions are curved such that the vortical flow of the primary wing continues outward and up to the second. The primary wing""s lift-induced vortical flow is directionally opposite to the normal pattern of vortical flow around the second wing. Both wings are swept the same direction and joined such that lower surface of the first wing transitions to upper surface of the second wing and the bottom of the first continues into the top of the second. Because interfacing lift-induced bound vortices of each adjacent wing pair rotate directionally opposite, unfavorable interference is produced. Geraci""s invention included a joined blade propeller which functions in a manner similar to joined wing systems, but this joined blade propeller suffered the same limitations inherent in conventional unmodified joined wing systems.
Zimmer (U.S. Pat. No. 4,090,681) utilizes two sets of wings forming a closed frame. All wings are rearward swept. The aft set of wings attaches to the fuselage at a lower level than front wings. The vertical fin does not support the wing. Wings are joined at the outer tips of each adjacent pair either by a flat plate or small rounded tip. There is no provision for optimizing the fluid-dynamic flow such that formed vortices are minimized or eliminated.
Ratony (U.S. Pat. No. 3,981,460) discloses an aircraft with swept back and swept forward wings that form a closed triangle or xe2x80x9cdiamondxe2x80x9d shaped frame in front elevation view. The wing is essentially a continuous loop and is supported at the roots only. In a second patent, Ratony (U.S. Pat. No. 4,053,125) shows fore and aft wing pairs joined at the tips either with a tank-like tip or a curved continuation of the first wing""s upper surface into the correspondingly opposite (i.e. the bottom) of the second. The surfaces are not linked corresponding surface to corresponding surface. Wings overlap somewhat producing greater than normal potential for fluid-dynamic interference and vortex shedding.
Miranda (U.S. Pat. No. 3,834,654) discloses an aircraft that uses forward swept rear wings and rearward swept forward wings that are connected by vertical panels forming a rectangular box configuration. Structural stiffness against side forces is limited in that it has no diagonal members. The vortical flow components of either forward foil of the pair would tend to create interference with the vortical flow component of each corresponding aft-located foil. Each said aft located foil is attached inboard at a location higher on the fuselage than said forward foil is attached. The vortical circulation produced by said forward foil would move upward and outboard, rotating around said forward foil from the root of said foil to the outer foil tips and around the vertical panel until it interfered with the lift-induced oppositely rotating vortical flow of said aft located foil. The counterrotating vortices produced interfere with each other. The result is disadvantageous lift-neutralizing effects on aircraft configured with this version of a joined wing system.
Wenzel (U.S. Pat. No. 4,146,199) demonstrates an aircraft comprised of an unconventional lifting fuselage having flat panel sides to which two wing pairs are attached. The rear wings are swept forward at negative dihedral, and the forward wings are swept rearward, each wing joining its adjacent neighbor wing at the tip. These wings are joined by a curved surface, somewhat horseshoe shaped in front or rear elevation view. As with the Miranda and Geraci designs, the outward travelling bound vortex of the front wing continues circulating around the wingtip union outward to finally interfere with the normal rotational direction of the lift-induced bound vortex circulating around the second wing.
Joined wing systems using any of the above-described techniques of fuselage attachment can be adapted to many existing aircraft with simple modifications and strengthening of structural members. The practical technology for development of joined wing aircraft is currently established in practice by NASA and by inventors who have contributed significantly to this technology, but the problem of successfully eliminating major amounts of vortex-induced drag has not been well resolved in previous inventions. What had been needed is a complement to the prior art that would resolve long-standing problems of vortex-induced drag and fluid-dynamic inefficiency inherent in fluid-dynamic systems. The problem of fluid-dynamic inefficiency and thus prevention of energy loss from fluid-dynamic drag has been only partially addressed by practitioners of the prior art.
This invention consists of joining adjacent fluid-dynamic foil segments by using mobius-like structures or segments of somewhat mobius-like elements to unite said adjacent fluid-dynamic foil segments so that there is a continuity of first fluid-dynamic foil surface into the corresponding subsequent fluid-dynamic foil surface.
When joining a first foil segment to a subsequent foil segment the top surface of said first foil segment is continuously joined to top surface of said subsequent foil segment and the bottom surface of said first foil segment is continuously joined to the bottom surface of said subsequent foil segment. These continuously joined surfaces translate vortical fluid-dynamic pressure flow from the first surface to subsequent surfaces such that major xe2x80x9cfreexe2x80x9d vortices are inhibited from forming at the outer tips of said first foil. The pressure-dynamic flow of the xe2x80x9cboundxe2x80x9d vortex circulating around said first foil can be thus translated by means of the moblus-like structure or segment of mobius-like structure to said subsequent foil surface. Said translated fluid-dynamic pressure flow tends to favorably intercept and instead of contradict, actually complement or augment the lift-induced circulating pressure-dynamic vortex bound around said subsequent foil surface. Some of this bound vortical energy may be converted to forward thrust by calculated arrangement of specific elements of this invention. The union between said first foil""s outer tip and said subsequent foil""s outer tip can be curved, twisted, bent, or canted for maximized induced drag reduction as needed for specific application and to meet the aesthetic requirements of the particular design being created or a unit can be retrofitted to an existing foil/body arrangement by developing the particular shape of mobius-like structure necessary for both complementing the particular design and achieving the specific fluid-dynamic effect and specific efficiency desired.
By maintaining continuity of cambered forward wing surface joined to corresponding rear wing cambered surface, this invention inhibits xe2x80x9cvortex interferencexe2x80x9d and xe2x80x9csheddingxe2x80x9d. As rudders, wings and elevators vary in shape, size, dihedral and thickness for structural, performance, or sometimes for aesthetic reasons, likewise variations in the appearance of this invention will manifest for the same reasons. Though different in appearance, each variation is fundamentally the same method of uniting foil surface to foil surface with one principle mode of function exclusive to the invention. While the principles of the invention is made clear in illustrative embodiment, it will become immediately obvious to those skilled in the art that many modifications of structure, arrangement, proportions, elements, materials, and components used in the practice of this invention can be particularly adopted for specific environments and operating requirements without departing from the principles of its operation and arrangement. It will be obvious to those skilled in the art that many modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.
The effect of using this method of utilizing moblus-like unions or segments of mobius-like structure for joining adjacent wings or fluid-dynamic foils is to produce one continuous vortical circulation pattern that does not shed into the free stream but instead stays in circulation from the first foil toward the tip, transitioning across the tip union and around the subsequent foil without the typical occurrence of vortices shedding into the freestream. When applied to aircraft structures using the joined wing system for example, the fuselage or rudder acts upon said circulation pattern as would a final end plate on a wingtip and does not allow this return fluid-dynamic flow to shed as a tip vortice. In effect this structure acts more closely like aerodynamic theory""s description of an ideal no-induced-drag xe2x80x9cinfinite wingxe2x80x9d than does a conventional or joined wing in spite of limited span of low aspect ratio.
Classical aerodynamic theory postulates that an infinitely long wing would produce absolutely no induced drag. Comparing the lift to drag (L/D) ratios of long-winged xe2x80x9chigh aspect ratioxe2x80x9d gliders with shorter winged craft having the same wing area but using smaller aspect ratio wings upholds the validity of this theory: Long, high aspect ratio foils produce less induced drag than shorter low aspect ratio ones. There is proportionally less vortex shedding on a high aspect ratio foil than on a low aspect ratio foil. One can infer that reducing or eliminating the production of free vortices created by lifting foils would greatly enhance fluid-dynamic efficiency of a set of fluid-dynamic foils. The effect of this invention in diminishing vortex shedding would be similar to the effect of increasing the aspect ratio of a wing without the normal problem of incurring major weight penalty by adding sufficient structure necessary to strengthen and stiffening an extended, more efficient wing.
Application of said invention would demonstrate function that is more fluid-dynamically efficient and more useable than existing systems. Said invention can be integrated into existing foil systems and designed compatible to particular shapes with function in mind, but also proportioned in harmony with an eye toward aesthetic appeal which is a realistic necessity for marketing a product or modification of an existing design. Said unions should appear xe2x80x9cintegratedxe2x80x9d with a specific aircraft design without changing the fundamental pressure translating function of said invention. Unions described herein should be adaptable to change of shape, proportion, arrangement, and combination in tandem or multiples. They should maintain integrity of function according to specific principles of operation described herein even if said union""s proportions are changed to aesthetically and functionally suit a particular aircraft configuration to which it is applied. Said invention""s universal application demands that it must be adaptable to rearrangement of elements and change of materials and components without departing from a principle mode of operationxe2x80x94whether employed singly or as multiples in tandem, and can therefore appear quite different in different applications, yet it will be the same invention operating according to said principle mode of operation, i.e. the favorable translation of fluid-dynamic flow from one foil segment to a subsequent foil segment by means of using said mobius-like structures or said segments of mobius-like structure to unite adjacent foils.
Said invention described herein uniquely complements the prior art and related inventions. Said invention can be directly adapted to most joined wing systems, similarly arranged propellers, and fluid-dynamic devices configured to utilize said principle mode of operation. The result is greatly improved fluid-dynamic foil efficiency and reduction of induced drag.
Properly utilizing vortical energy potential available at the outer tip of a lifting foil system produces these results: minimal induced drag, positive vortical translation, extraction of forward thrust from differential pressure flow, and efficient translation of directionally-correct vortical circulation around the wing. The advantages for aircraft are: the effect of high aspect ratio wings using shorter wing-spans, less structural weight, greater wing stiffness, and greater compactness. By utilizing panels that unite one or more foil segments to another (i.e. when using more than two foils, uniting the subsequent foil and the next subsequent, etc.), a more efficient path for vortical flow transition is formed. This can be accomplished by arranging panels such that they give the appearance of being doubled over or bent. These panels unite two or more foil segments so that corresponding opposite surfaces of both foils are continuously united such that upper surface of the first foil segment transitions into upper surface of the subsequent foil segment, and opposite surface of said first foil transitions into opposite surface of said subsequent foil segment. These panels which unite foils can be molded, constructed, or shaped to be efficient, strong and aesthetically balanced. Specific portions of these panels with a shape that appears doubled over result in a load-bearing union that favorably translates vortical flow from a primary foil to one or more successive ones. This invention is meant to be used as a universal upgrade for specific wing systems, greatly improving the efficiency of its operation, resulting in energy conservation.
It is intended that this invention be integrated with existing configurations either during manufacture or as accessory retrofit. By varying proportion and combination of elements without departing from the basic function and spirit of the invention, it can be integrated into different aircraft designs to maximize efficiency and maintain style continuity.
This invention""s potential application goes beyond xe2x80x9cjoined wingxe2x80x9d aircraft. When properly configured for each specific application, singly, in tandem, or in multiples, it can greatly improve efficient operation of varying aircraft such as biplanes with joined wingtips, joined tip canard systems and aircraft having rear tail planes joined to wingtips.
This invention relates to aircraft specifically and in general to all similar fluid-dynamic devices that create lift or thrust by use of one or multiple foils. Application of the moblus-like union of foils is not limited to aerodynamics, but as well to other fluid-dynamic devices such as hydrofoils and fluid-dynamic blades or rotary blade systems that extract energy from or add energy to the fluid medium they traversexe2x80x94which is the essence of fluid-dynamic interraction between foils and fluid mediums.
One potential for application is in use with rotary wings such as those found in helicopters. A set of rotating foils typically used on a helicopter has blades which are essentially lift and thrust producing foils which rather than remain fixed on a fuselage, instead rotate about an axis, but still function as foils producing lift. In practice such foil sets can be correctly defined by observing their principle mode of operation. Rather than being something other than foils that are simply wings or foils that are just propellers or foils that are only rotary wings, in essence all wings, rotary wings, or propellers are the same entity. They are simply lifting foils operating in various attitudes and with different applications, using the same principle mode of operation. Some craft have rotary wings that once in flight are transitioned from horizontal to vertical orientation, suddenly becoming propellers rather than as formerly, rotary wings, until there is reversion to previous attitude for landing. These foil sets have not changed in function, structure, or mode of operation other than orientation in space producing forward thrust rather than lift. Forward thrust created by blades is in essence simply horizontally applied lift. The terms thrust and lift by popular definition are considered dissimilar, but as applied to fluid-dynamic foils in practice and observation, they are identical except that propellers are applied in roughly a horizontal plane, creating horizontal lift while spiraling through the fluid medium in which they operate. Wings likewise operate in roughly a horizontal plane, do not spiral but utilizing fluid-dynamic flow over foil surfaces create upward lift while travelling in a linear direction. The rotary wing likewise produces lift in roughly the upward direction, as does the wing, but spirals through the medium as does the horizontally travelling propeller. Gravitational force is the only other major factor that affects them both in similar and dissimilar ways simultaneously. In the first case, rotary wings and conventional lifting foils generally create lift in 180 degree opposition to gravity, and in the second case, propellers and fans create lift largely in the horizontal plane at approximately a 90 degree opposition to the force of gravity. In essence, a lifting foil is the same device whether it is travelling upwardly, horizontally, or spiraling through the medium it traverses.
Foil-produced lift and foil-produced thrust are in essence the same thing. The principle of operation is the same in spite of differences of terminology we have applied to the phenomenon because of the influence our prevailing cultural orientation has had upon our language. Our language useage influenced by our culture can mislead our perception of technology. When a foil surface is passed through a fluid, pressure differential influences the foil to move toward the direction of the least pressure or foil shape causes pressure differential on opposite sides of the foil. The same principle governing foils interacting with fluids applies whether the result is horizontal movement produced because force moves the foil along a spiral path; it is the same principle governing when horizontal linear force applied to a foil produces lift which is perpendicular to the plane in which the force is applied; it is the same principle governing when vertical movement is produced because force moves the foil along a spiral path. Foil-produced lift and foil-produced thrust are the same phenomenon, the extraction of energy from fluid-dynamic flow, in spite of our language.
Rationally, application of this invention would be to fluid-dynamic foils in general, because they are by means of the pressure differential creating lift or thrust, which in essence is the same thing.
Mobius-like unions or segments of mobius-like structures can be used to join fluid-dynamic foils that are xe2x80x9csplitxe2x80x9d into separated segments and united again in order to increase fluid-dynamic efficiency of the united foil system. These foil segments, though rejoined to the original foil segment, are equivalent to separate foils joined to one another, in that they are separate foil segment which are joined with the initial foil. In appearance they look to be miniature joined wing-like structures on the tips of a conventional wing, and they are in essence the same thing, just terminating differently, because they function according to the same operating principle of this inventionxe2x80x94that of redirecting fluid-dynamic pressure flow by maintaining continuity of corresponding surface to corresponding surface when joining pressure-dynamic surface to subsequent pressure-dynamic surface.
It is also possible to utilize this invention to redirect fluid-dynamic pressure through channels or pathways formed by moblus-like unions joined to foils and foil segments. This redirected fluid-dynamic pressure flow can be utilized to cool propulsion systems, engines, and other devices. This redirected pressure flow can also be used to supply and augment pressure used or created by propelling devices and engines. Additionally foil systems utilizing mobius-like structure to unite them can both supply surface burning propulsion devices with pressure-dynamic flow, and in some cases even be the specially prepared surfaces upon which the fuel ignites and burns.
In some cases it is desirable to add xe2x80x9clips,xe2x80x9d or xe2x80x9ccuffsxe2x80x9d and extensions to existing mobius-like structure in order to improve fluid-dynamic function and to enhance creation of thrust from redirected fluid-dynamic pressure flow. It is also possible to extend said lips or cuffs into longer, more tubular shapes while still maintaining the principle mode of operation of this invention, namely translation of pressure-dynamic flow from one foil segment to another fluid-dynamic advantage.
Mobius-like structure can be used to join said foil segments or said foils to helical-shaped foil segments which are xe2x80x9cwrappedxe2x80x9d directionally opposite to the rotational direction normal to that of a shedding vortex. This causes pressure-dynamic flow to be turned inward and opposite the direction normal to rotation of a shed vortex. Greater thrust potential is achieved and vortices are inhibited from forming as they would with use of conventional foil surfaces not having modification. This helical curved foil segment joined to a previous foil segment would also lend itself to surface burn technology. The high pressure from the lower foil surface would supply the burn surface with fluid-dynamic pressure flow, and the surface formed would be designed to function as a burn surface. Thus combustion would occur directly upon specific parts of the configuration formed by said mobius-like structure joining foils and subsequent foil segments, and consequently thrust would be produced. The mobius-like structure joining foils described herein would easily lend itself to adaptation of this kind of technology. Such technology combined with this invention has application to wings, helicopter blades, propellers, and other devices which are likewise foil-based fluid-dynamic systems operating in a fluid medium.
This apparatus has a wide range of potential usage and attachability to an almost unlimited array of structures, particularly those that function in fluid media, and can be joined to various intermediate attachment structures: transportation and vehicular structure in some cases; some automotive systems utilizing foil structure; aircraft structure (which includes ring wings, biplanes, monoplanes, canard aircraft, C wing structure, joined wing, channel wing, boxplane, lifting fuselages and others); various foil structures and attachment methods (joined foils, intermediate foils attached to other surfaces, foil tip and root structure, apparatus tied directly to spar structure, winglets, joined tips, airfoil tip structure, ducted fans, rotary wings, foil structure split into segments, propellers, swept wings, straight wings, delta wings, and cambered surfaces generally including rudders and elevators). Use of these unions results in:
A. Mobius-like fluid-dynamic structure which will modify the vortex shedding characteristics of foil tips.
B. Structurally rigid unions of foil segments and complementary fluid-dynamic shapes that modify fluid-dynamic pressure flow.
C. Mobius-like structure that modifies segmented foil tips so that they become more efficient fluid-dynamic shapes.
D. Creation of fluid-dynamic unions by uniquely reuniting segments of an individual segmented foil.
E. Fluid-dynamic structural unions comprising segments of separate foils that are rejoined for fluid-dynamic advantage.
F. Creation of structure and specific fluid-dynamic shape using mobius-like unions which direct pressure from one foil segment to subsequent foil segment such that favorable fluid-dynamic interaction between these foil segments is made possible for purposes of drag reduction (if adapted and designed correctly this invention has potential to be united with and improve the function of many of these structures: structure intended to extract thrust by means of fluid-dynamic function, structure intended to produce lift, structure intended to affect fluid-dynamic pressure differentials, structure intended to inhibit pressure differential from equalizing, structure intended to impel fluids, structure intended to transition fluid-dynamic flow, structure intended to cause augmentation of fluid-dynamic flow and structure intended to direct fluid-dynamic flow).
G. Mobius-like joining structure used to develop systems which can utilize combinations of foil segments, unions, complementing panels, and surfaces used for directing fluid-dynamic flow, for reduction of drag, for vortex reduction, for creating surfaces, for special-purpose flow functions, and incorporating drag reducing shapes to augment fluid-dynamic function (these forms of structure can be intended to produce directed thrust, to increase directional thrust, extract thrust by means of fluid-dynamic function, to inhibit pressure differential from equalizing, or to impel fluids. Any foil-related structure having material arrangement, fluid-dynamic element, and designed or proportioned components has potential for combination with this invention including crash protection structure having fluid dynamic characteristics, foils with end plate attachment or structure attached, such as loops, continuous structure, and structure having various aspect ratios).
H. Incorporation of added moveable control surface elements for directing flow and for modifying fluid-dynamic function used as a means to direct fluid-dynamic flow for lift augmentation, maneuver and flight control (structure for directing fluid-dynamic flow, structure for controlling fluid-dynamic flow, control apparatus structure, structure used for affecting fluid-dynamic flow; structure for affecting directional control, structure for affecting lift augmentation, structure for lift control, structure for affecting conventional maneuver, structure for affecting non-conventional maneuver).
L. Creation of mobius-like unions which, when combined with fluid-dynamic components, channel fluid-dynamic pressure to specific areas for utilization by fans, blades, engines, or other devices to propel fluids, for cooling, for use as augmenting fluid-dynamic pressure flow for propulsion purposes, or to be used as directed pressure flow to external burn surface propulsion systems (propelling structure, fluid-dynamic lift-producing structure, fluid-dynamic structure involved in thrust production, structure connected to propulsion devices or systems, rotating structure having fluid-dynamic elements, structure which extracts pressure-dynamic energy from fluid-dynamic flow, structure which utilizes foil structure to extract lift from fluid-dynamic flow, structure which translates fluid-dynamic pressure flow to another structure, structure translating fluid-dynamic flow to a subsequent sector of itself, fluid-dynamic structure passively activated by fluid-dynamic flow, foil structure actively modifying or affecting fluid-dynamic flow, helicopter structure, propeller blade structure, structure used for ducting fans, fan blade structure, pump structure, wind-operated foil-bearing fluid-dynamic structure, structure which embodies a plurality of said apparatus).
J. Using mobius-like structure to join foil segments to subsequent helical or spiral, or otherwise variously shaped foil segments as means of inhibiting vortex production by forcing fluid-dynamic pressure flow to rotate in a direction opposite the direction normal to a shedding vortex and to inhibit vortex shedding (these foil-related structures are intended to produce specific fluid-dynamic functions creating structure intended to modify vortex formation including vortex generator structure, structure intended to modify vortex intensity, structure intended to reduce vortex production resulting from fluid-dynamic function, and structure intended to reduce vortex drag).
K. Foil segments can be joined by mobius-like structural elements that have xe2x80x9clipsxe2x80x9d or xe2x80x9ccuffsxe2x80x9d extended from existing fluid-dynamic elements used as a means to augment efficiency and performance efficiency of foils and foil segments joined by said moblus-like structure or unions.
L. Having mobius-like structural elements join foil segments to subsequent helical (spiral) or variously shaped foil segments forming a fluid-dynamic surface components of a propulsion means used to produce surface burning propulsion (there are many composite systems having function to which variations of this apparatus can be attached for improving their operation: structure for cooling, structure used to augment pressure used by propelling devices and engines, structure of on-surface-bum devices which produce thrust directly on a fluid-dynamic surface, structure using on-surface-burn technology, structure used as a means of containing surface burn combustion).
M. Composite systems comprised of mobius-like structure joining foil segments that direct fluid-dynamic flow for developing thrust, or for use in other purposes that would utilize directed fluid-dynamic pressure from these unions (there are other structures for various fluid-dynamic purposes having diverse characteristics to which this apparatus may be attached for fluid-dynamic function purposes: structure having panel area which operates in a fluid medium, structure having curved shape which operates in a fluid medium, structure having shapes which modify fluid-dynamic pressure flow, the apparatus mounted to structure in tandem, the apparatus mounted to structure in multiples, foil structures that operate in fluid medium, foil-based systems that operate in a fluid medium, scale model structure, marine structure, boat structure, hydrofoil structure, underwater vehicle structure, structure which when combined with said apparatus forms loop or channel shape, foil structure having helical shape, multiple connections in array comprised of foil structure and said apparatus, structure comprised of foil segments and surfaces, structure comprised of foil segments and attached panels, structure comprised of foil segments and unions, structures used to reduce fluid-dynamic drag, structures used for creating new fluid-dynamic surfaces added to existing structure, structures incorporating drag reducing shapes, structure used as projectile or arsenal means, structure temporarily or permanently attached to projectile or arsenal means. There are other categories of foil-based devices having structure, having some fluid-dynamic characteristics, operating in fluid medium, and having the potential for application of this apparatus. These include: foil segment-bearing structure having recreational use; foil segment-bearing structure having commercial use; foil segment-bearing structure having transportation use; foil segment-bearing structure having military use; foil segment-bearing structure having decorative use; foil segment-bearing structure having presentation purposes; kite structure; toy structure; floating cube electric powered kite structure; floating cube aircraft structure; parachute structure; paraglider structure).
N. Fluid-dynamic structural elements which are joined to form surface continuity from a first element surface to surfaces on subsequent elements, creating shape which separates high pressure areas from low pressure areas, thus keeping high pressure flow transitioning across said subsequent surfaces, recirculating it over high pressure areas comprised of said first surface joined to subsequent surfaces which in turn are rejoined to first surface. By keeping high pressure flow on high pressure surfaces longer said fluid-dynamic elements which are joined are used as a means to favor thrust and lift being produced rather than production of shedding vortex. Foil-created high pressure is thereby inhibited from equalizing with low pressure flow and shedding as a vortex, but instead is caused to recirculate with this fluid-dynamic energy being converted to directional thrust and additional lift by the arrangement of said fluid-dynamic elements.